Closure cap for bottles, jars, and the like



July `1 1947 v L.. 1*.cRABaE Er m. '2,423,295

CLOSURE CA'P FOR BOTTLES, JARS, AND THE LIKE med Feb. 19. 194e PatentedJuly 1, 1947 CLOSURE CAP FOR BOTTLES, JARS, AND THE LIKE Lindsay T.Crabbe, Chicago, Ill.,

Angeles, Phoenix Metal Cap Company, corporation of New York Lathrop, Los

and Donald C. Calif., assignors to Chicago, Ill., a

Application February 19, 1946, Serial No. 648,592 2 Claims. (Cl. 215-56)provements in a closure means for bottles, Jars and the like, and moreparticularly a closure means which will vent when the internal pressuredeveloping in the container becomes excessive.

An object of the invention is to provide a closure means of the abovetype which includes a metal cap wherein the top portion thereof is sodimensioned and shaped that it will flex outwardly when subjected to aninternal pressure above a' predetermined degree and relieve pressure ofthe cap on the sealing gasket sufficiently to permit venting.

A further object of the invention is to provide a closure means of theabove type wherein the ilexing of the top is within the elastic limitsof the metal so that when the internal pressure drops to nearatmospheric pressure, said top portionwill spring back to its initialposition and form a very satisfactory liquid-tight seal.

These and other objects vwill in part be obvious and will in part behereinafter more fully disclosed.

In the drawings:

Figure 1 is a view partly in vertical section of` a closure meansembodying the Aimprovements as initially applied to a container forsealing the same;

Figure 2 is a view similar to Figure 1 but showing the top portion ofthe container as flexed outwardly by an excessive internal pressure soas to relieve the pressure of the cap against the sealing gasketsufficiently to permit the gases to escape between the gasket and thelip of the bottle and thus vent the container;

Figure 3 is a perspective view of the upper end of a container showingthe sealing lip as notched at intervals at the outer sidethereof tofacilitate venting;

Figure 4 is a view similar to Figure 1 but show-4 ing the improvedclosure cap applied to a container having a notched sealing lip as shownin Figure 3;

Figure 5 is a view similar to Figure 4 but show ing the top portion ofthe container as flexed outwardly by an excessive internal pressure soas to relieve the pressure of the cap against the sealing gasketsumciently to permit the gases to escape through the notched portions inthe lip of the bottle.

The present invention has to do with a closure means for containers andin particular a container having a neck portion terminating in a fiatsealing lip. The closure means includes a sealing gasket in the form ofa disk which may be made of any suitable gasket material and is sodimensioned as to extend all the way across the mouth of the Jar andoverlie the sealing lip thereof.

The sealing gasket is pressed against the lip of the container forsealing the same by a metal cap which is provided with a dependingskirt. The skirt is secured to the neck of the bottle by any suitablemeans. The top of the cap is formed with an annular flat portion whichextends Vfrom the skirt to a point just inside of the lip of thecontainer. The central portion of the cap is concaved inwardly all theway from one side to the other of the annular fiat portion. Thisinwardly concaved portion, when the cap is applied to the container,extends slightly into the mouth of the container and forces the gasketilrmly against the lip of the container and thus forms a tight seal.

When the internal pressure in the container develops to a predetermineddegree, the concave portion of the top will be forced outwardly andinverted to a certain extent into an outwardly bulging portion whichwill lift the inner part of the annular fiat section 'and relieve thePressure of the cap against the gasket at the inner side of the lipthereof and, to someextent, outwardly therefrom, so that the gases underthe developed pressure will work outwardly inbetween the gasket and thelip of the container and escape, and thus the container is vented.

The metal of the cap is so dimensioned that the flexing of the sameoutwardly by the internal pressure is within the elastic limits of themetal and, therefore, when the internal pressure drops so as to approachatmospheric pressure, the metal will spring back to its initial positionand force the gasket against the sealing lip so as-to form asatisfactory liquid-tight seal. This venting of the container by theflexing of the top portion of the cap is very satisfactory when used inconjunction with the standard finish of the lip of the container. It is,however, sometimes desirable to provide cut-away portions at intervalsin the outer portion of the container lip to facilitate venting.

Referring more in detail to the drawings, the

container illustrated is of glass and is intended to represent a bottleor a. jar. The container is indicated at I and is provided with a neckporr0 tion 2. The neck 2 terminates in a flat sealing lip 3 which, asshown in Figures 1 and 2, is the standard bottle finish. On the outerface of the neck of the bottle is a standard thread or lug 4.

The closure means includes a sealing disk 5 which may be of any suitablegasket material.

This gasket extends all the way across the mouth and overlies the lip ofthe bottle and preferably extends beyond the lip so as to provide adiameter of gasket which will cause the gasket to be retained in aclosure cap as a unit therewith. The closure means includes a metal cap,indicated as a whole at C. This cap is provided with a depending skirt 6which is formed with a thread adapted to cooperate with the thread orlug 4 on the neck of the container. This is the usual form of means forsecuring the cap to the bottle. It will be understood that othermechanical ways may be employed as the securing means for holding thecap attached to the bottle as this securing means forms no part of thepresent invention.

The top of the cap is formed with an annular ilat section 8 whichextends inwardly from the skirt and terminates just inside of the lip 3of the bottle. This ilat portion of the cap lies initially in a planewhich is parallel with a plane containing the outer face of the lip ofthe bottle. The top portion within this annular flat section is concavedinwardly as indicated at 9 in the drawings. This concaved portion is ofa diameter slightly less than the diameter of the mouth of the bottle.When it is desired to seal the bottle, the cap with the gasket thereinis turned onto the neck of the bottle and this will force the gasketagainst the lip until a tight seal is produced all the way across thelip by the flat section of the cap pressing thereagainst. The concaveportion 9 of the top will curve the sealing disk inwardly, bringing itinto tight contact with the inner edge portion of the tip. This sealingof the bottle is clearly illustrated in Figure 1 of the drawings.

The metal constituting the top of the cap is so dimensioned that whenthe internal pressure becomes excessive, the concaved portion will beforced outwardly, and the central portion thereof, at least, will becomeconvexed. This bulging. of the central portion of the cap outwardly willlift the inner portion of the annular flat section of the cap andrelieve the pressure of the cap against the gasket at the inside of thelip so that gases under the excessive internal pressure will passbetween the gasket and the lip and escape, as indicated by the arrows inFigure 2. This outward bulging of the central portion of the cap iswithin the elastic limits of the metal, and when the internal pressuredrops to near atmospheric pressure, then the top will spring backsubstantially to its initial position shown in Figure l ar. reseal thecontainer so as to provide a very satisfactory liquid seal.

In Figure 3 of the drawings the lip of the bottle is shown as providedwith cut-away portions l0. There are three of these cut-away portionsand they are shown as rectangular in shape. This notch formed by cuttingaway the lip of the bottle extends all the way to the outer edge of thelip but terminates short of the inner edge of the lip so that there ise, continuous portion Il of the sealing lip extending all the Way aroundthe mouth of the bottle. The improved closure cap, which has beendescribed as used in connection with a standard nnish, wherein the lipis smooth and unbroken throughout the entire extent, may be used withadvantage in connection with the notched lip shown in Figure 3. InFigure 4 the cap is shown as applied to a bottle having a notchedsealing lip. The cap pressing on the gasket will force it into tightengagement with the lip and there will be a continuous unbroken sealingline all the way around the inner edge portion of the lip indicated atIl in Figure 3.

In Figure 5 of the drawings the cap is shown as subjected to a developedinternal pressure which becomes excessive and which will force thecentral concaved portion of the cap Aoutwardly in the same manner asdescribed in connection with Figure 2. This outwardly bulging centralportion, incident to the gas pressure from within, will lift the innerportion of the annular section 8 so as to relieve the pressure of thegasket against the inner portion of the lip and thus the gases willwedge in between the gasket and the lip and gradually escape into thenotches and thus bring about a venting of the container. Here again,when the internal pressure drops to near atmospheric pressure, the topof the cap will spring back into substantially its initial shape, asshown in Figure 4, and bring about a resealing of the bottle, whichproduces a very satisfactory liquid.- tight seal.

While the invention has been described as particularly adapted for usein connection with a glass container such as a bottle, it will beunderstood, of course, that it will have advantages in connection withcontainers made of plastics or any other suitable material.

It is obvious that many changes in the details of construction andshaping of the parts may be made without departing from the spirit ofthe invention as set forth in the appended claims. It is essential thatthe metal cap shall be so shaped and dimensioned that when initiallyapplied to the container it will effectively seal the container and alsoso shaped and dimensioned that when the internal pressure develops to anexcessive degree, the central portion of the cap will be caused to bulgeoutwardly and deform within the elastic limits of the metal sufficientlyto relieve the pressure of the gasket against the inner portion of thelip of the container and thus permit the gases to escape, and further,it is desirable that, when the internal pressure drops to nearatmospheric pressure, the deformed top portion of the cap shall springback into substantially its initial position and reseal the container soas to make an effective liquid-tight seal.

We claim:

l. A closure cap for containers having a neck terminating in a mouthsurrounded by a lip comprising a resilient iiexible metal top and adepending skirt having means whereby the cap may be secured to the neckof the container and a sealing gasket within the cap adapted to extendacross the mouth of the container and overlie the sealing lip thereof,said top in the region which is adapted to overlie the mouth of thecontainer being curved inwardly and biased so as to remain in saidinwardly curved position and cooperate with the remainder of said top inpressing the gasket against the sealing lip of the container whenapplied thereto and so long as the pressures on the opposite sides ofthe top are substantially equal, said entire top being resilientlyiiexible upwardly when the internal pressure of the container becomesexcessive and exceeds the external pressure on the top whereby torelieve the pressure of the gasket against the lip and permit venting,said iiexing of the tcp being within the elastic limits of the metalwhereby said top will return substantially to its initial position whenthe internal pressure becomes substantially1 equal to the externalpressure for resealing the container.

2. The combination of a container having a :Maanen neck terminating in amouth surrounded by a sealing lip, the inner portion of saidA lip beingcontinuous and the outer portion being notched l extending across themouth of the container and overlying the sealing lip thereof, said topin the region which overlies the mouthful the. container being curvedinwardly and biasedso as to remain in inwardly curved position andcooperate with the remainder o! the top in the pressing of the gasketagainst the sealing lip of the container when applied thereto and solong as the pressures on the opposite sides of the top are substantiallyequal, said entire top being reslliently flexible upwardly when theinternal pressure ot the container becomes excessive and exceeds theexternal pressure on the top whereby to\relieve the pressure of the capand gasket against the lip and permit the gases within the container topass between the gasket and the lip and escape through said notches,said iiexing of the top being within the ensue limits of the metalwhereby said top will return substantially to its initial position whenthe internal pressure becomes sub stantially equal to the externalpressure for resealing the container.

LINDSAY T. CRABB. DONALD C. LATHROP.

REFERENCES CITED The following references are of record in the ille otthis patent:

Uizrrnn STATES PATENTS Great Britain Feb. 13, 1931

